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Moisture Load and Dehumidifier Capacity Calculator

Model a daily moisture mass balance from dry-air flow and humidity ratios, then compare assessed removal needs with documented equipment capacity.

Use this result well

Inputs that matter
Dry-air mass flow (kg dry air/h), Inlet humidity ratio (kg water/kg dry air), Target humidity ratio (kg water/kg dry air), Daily flow operating hours, and 8 more
Output to expect
Daily moisture mass balance, Dehumidifier capacity and runtime check
  • Check the units and required inputs before comparing results.
  • Keep the assumptions with a copied result so you can reproduce the calculation later.
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Reference & details

How it works

Daily moisture mass balance

Estimate one day's ongoing moisture balance from a documented dry-air mass flow, inlet and target humidity ratios, operating hours and separately estimated internal/other moisture sources. Humidity ratio is kilograms of water per kilogram of dry air; a relative-humidity percentage is not an interchangeable input.

Net kg/day = dry-air kg/h × (inlet − target humidity ratio) × hours/day + internal kg/day + other kg/day; required removal = max(0, net).

Dehumidifier capacity and runtime check

Compare a separately established daily moisture-removal need with equipment performance at matching temperature and humidity. Enter a documented 24-hour removal rate and your available operating hours. The runtime scaling assumes that rate can be sustained while operating.

Available L/day = stated 24-hour capacity × unit factor × operating hours ÷ 24; difference = available − required.

Updated: September 2026

Example Scenarios

The built-in example is an arithmetic illustration. Replace it with your own verified measurements or planning assumptions.

→ 10.64 kg/day modeled moisture removal

The built-in example is an arithmetic illustration. Replace it with your own verified measurements or planning assumptions.

→ 1.36 L/day capacity difference

FAQ

No. The mass balance needs humidity ratios, dry-air mass flow and separately assessed moisture sources. Equipment capacity must apply at the relevant temperature and humidity; initial dry-down is a separate issue.

Use the actual source documents, units and operating conditions shown in the selected mode. Replace illustrative examples with your records, enter explicit zeros only where valid and retain unresolved assumptions.

Choose Save planning case for local history. Copy MD retains current inputs, notes and interpretation; Download CSV exports the result breakdown. Export a separate copy before changing devices or clearing browser storage.

About Moisture Load and Dehumidifier Capacity Calculator

Estimate one day's ongoing moisture balance from a documented dry-air mass flow, inlet and target humidity ratios, operating hours and separately estimated internal/other moisture sources. Humidity ratio is kilograms of water per kilogram of dry air; a relative-humidity percentage is not an interchangeable input. Compare a separately established daily moisture-removal need with equipment performance at matching temperature and humidity. Enter a documented 24-hour removal rate and your available operating hours. The runtime scaling assumes that rate can be sustained while operating.